AUTONET TV

Differential Essential (Differential Fluid Exchange)

What's the dif? To an automotive technician, it's the differential, a part of your vehicle that helps direct power from the engine to the wheels.  The differential is a gearbox that enables the drive wheels to turn at different speeds (they do that when you turn).  

Inside the differential is a fluid that makes sure those gears and other parts are lubricated since there are a lot of metal moving parts in there.  (Your vehicle may have more than one differential in it depending on the drivetrain.) 

As you can imagine, it's important that the lubricant in those differentials do its job.  Otherwise, the gears may be damaged by heat and friction. The more you drive your vehicle, the more likely it is for that lubricating fluid to break down.

So, it's important to have the differential fluid exchanged every so often.  Your vehicle's manufacturer recommends how often your model should have that done, but a common interval is every 30,000-60,000 miles/50,000 km-100,000km.  Regular exchange of differential fluid can reduce premature wear of the gears inside.

Scheduled maintenance goes a long way to preventing differential problems, but sometimes when they begin to fail, you may hear the vehicle sounding a little louder than usual where the differentials are located.  

When it comes to changing the differential fluid, some have a drain plug in them. Others require the entire cover to be removed to drain the fluid.  There are often gaskets that must be changed at the same time to make sure there are no leaks.
Now when someone asks you, "What's the dif?" You’ll know how essential the differential is and how to keep it running in top shape.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com

A Sticky Brake Situation (Parking Brake Service and Maintenance)

We've all been there.  You park your vehicle on a steeper than usual hill and worry about it rolling down while you're running your errands.  So you decide you'll use the parking brake.  When you get back, you release the parking brake, hit the ignition, put it in gear and—uh, oh—you can feel the parking brake is still on.  It's stuck.  What do you do now?

Welcome to the world of infrequently-used parking brakes.  Yes, they do stick for several reasons. It's common for components to corrode and get locked up.  Sometimes if you have applied it extra hard, it can jam.  Could be a rusty cable, could be a spring that doesn't return the brake to its disengaged position.  Some pieces just break when they're stressed for the first time in a while. A caliper or the pivot arm it's on can also stick.

There are a few things you can try to unstick it.  Carefully rock your vehicle by putting it first in drive and then reverse.  You have to be careful doing that, though, because sometimes you can damage the transmission.  You can try working the parking brake control a few times to see if that will loosen the corrosion.  If you can't unstick it, you can try driving slowly a short distance to a repair facility near you.  Sometimes it won't cause damage to the brakes but it depends on how tightly the parking brake was applied and what was stuck.  You may also have to have your vehicle towed to a repair facility.

In any case, once you've seen these symptoms, have your vehicle brakes looked at by a professional who can fix the root of the problem.  Better yet, don't let your vehicle get in this condition; regular maintenance and inspections by a trained technician should prevent you from getting in a jam somewhere thanks to a stuck parking brake.  You could use a "brake" like that.

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com

Busted! Air Conditioning (Air Conditioning Maintenance)

Your vehicle's air conditioning is something you count on when the weather heats up.  But there's bound to be a day when you turn it on and one of these things happens:

• Only warm air blows out
• Cold air starts blowing out but then it turns warm on its own
• It's not blowing air at all
• It blows smelly air out

Some people are tempted to try to make the diagnosis—and the repair—on their own.  They think it's just run out of refrigerant and they can pick up a can at a local auto parts store and re-charge it.   If only it was that easy.

A vehicle's air conditioning system is complex and made up of many parts.  A compressor, evaporator, condenser, tubing, hoses, sensors, valves… the list goes on and on.

Each of these components could be the reason for the problem.  It could be a leak that's letting the refrigerant escape, but simply re-charging the system hasn't fixed the problem. You have to find the source of the leak and fix it. Service facilities have a device called a "sniffer" which can sniff out refrigerant chemicals. And they can use black light to locate refrigerant that has an ultraviolet dye in it. 

But often other components wear out; blower motors go bad, resistors blow, tubes clog, compressors fail. And diagnosing that takes training and special equipment you'll find at your service facility.

One other thing to keep in mind.  It's always better to catch any problems in the air conditioning system before it fails. Ask your service advisor about having

the A/C checked as part of the vehicle's maintenance.  That's the cool way to go. 

McLearen Shell
3043 Centreville Road
Herndon, VA 20171
(703) 318-7744
http://www.mclearenshell.com